Apparatus for assemblying idler rolls and the like

ABSTRACT

A machine for assemblying and heading idler rolls and the like, which rolls embody a tubular shell, a head in each end of the shell and preferably, a centrally disposed grease tube connected at each end to centrally disposed openings on the inner sides of the heads. The apparatus embodies means to place a grease tube in the outer shell, means to position the heads adjacent the ends of the shell, mandrels which enter the shell from both ends, passing through the heads and entering the grease tube to center the heads and tube relative to the shell, and means to press the parts together. At another work station the ends of the shell are rolled or formed over, thus to secure the parts together. The machine is adjustable to fabricate rolls of different lengths.

United States Patent [191 Hooper APPARATUS FOR ASSEMBLYING IDLER ROLLSAND THE LIKE Homer Hooper, Winfield, Ala.

[73] Assignee: Continental Conveyor andEouip-j we! Q mran Winfi.ld .la-,-.a

22 Filed: Sept. 5, 1972 211 App]. No.: 286,036

Inventor:

[56] References Cited UNITED STATES PATENTS 2,655,718 10/1953 Haegele29/201 Nov. 27, 1973 Primary Examiner-Thomas H. Eager Attorney-Hugh P.Carter et al.

[5 7] ABSTRACT A machine for assemblying and heading idler rolls and thelike, which rolls embody a tubular shell, a head in each end of theshell and preferably, a centrally disposed grease tube connected at eachend to centrally disposed openings on the inner sides of the heads. Theapparatus embodies means to place a grease tube in the outer shell,means to position the heads adjacent the ends of the shell, mandrelswhich enter the shell from both ends, passing through the heads andentering the grease tube to center the heads and tube relative to theshell, and means to press the parts together. At another work stationthe ends of the shell are rolled or formed over, thus to secure theparts together. The machine is adjustable to fabricate rolls ofdifferentv lengths.

9 Claims, 20 Drawing Figures Patented Nov. 27, 1973 3,774,282

4 Sheets-Sheet 1 Patented Nov. 27, 1973 4 Sheets-Sheet 2 Patented Nov.27, 1973 4 Sheets-Sheet 3 Patented Nov. 27, 1973 3,774,282

4 Sheets-Sheet 4 E I? E15 15 V [Ill/[j] I I I I I I I I I I I Y/ YI/l/l// [A TEMPE/T14) I I! /'//r/ /I/ //////J APPARATUS FOR ASSEMBLYINGIDLER ROLLS AND THE LIKE My invention relates to apparatus forassemblying idler rolls and the like of the kind having an outer tubularshell, heads in the ends of the shell, and, in some cases, alongitudinally extending grease tube connected fluid tight to centrallydisposed bores in the heads.

One object of my invention is to provide an idler roll assemblying andheading apparatus in which, at one work station, a grease tube isinserted loosely into a horizontally disposed roll shell, and upontransfer to subsequent work stations the grease tube is brought intoaxial alignment with the shell, the heads are then pressed into the endsof the shell and connected to the ends of the tube, and at anotherstation the ends of the shell are rolled over or formed about theperipheries of the heads, thus to secure the parts together.

Another object is to provide apparatus of the character designated whichis capable of fabricating rolls of different lengths, this preferablybeing accomplished by mounting one side of the machine for movementrelative to the other.

Another object is to provide apparatus of the character designated inwhich the work pieces are transferred from work station to work stationby means of a walking beam type mechanism capable of accuratelypositioning the work pieces in proper relation to the respective deviceswhich are to operate thereon.

Generally described, my invention contemplates apparatus which embodiesessentially three work stations. At the first station a blank roll shellhas inserted thereinto, to lie eccentrically therein, a grease tube longenough for its ends to be press fitted into the inner concentric boresof a pair of heads or hubs. The thus assembled roll shell and tube arethen moved to the second work station. Means here is provided toposition the roll heads in generally axial alignment with the shell.Mandrels having sections of suitable diameter now move into thecentrally disposed bores of the heads, pushing them into-the ends of theshell. At :the same time, the inner, reduced ends of the mandrels havingentered the ends of the grease tube,.bring the grease tube concentricwith the shell and bores of the heads, so that concomitantly with theinward pressing of the heads into the ends of the shell the ends of thetube are inserted into the appropriate bores therefor on the inner,centrally located portions of the heads. The thus assembled parts arenow moved to the third work station at which the ends of the shell arerolled over thus to secure the heads in place. The completed roll maythen be moved to a discharge station. Also, as each work station isvacated an on-coming workpiece from the preceding station is placedthereon, whereby a continuing flow of workpieces is presented to thestations where the several operations take place, increasing theproduction rate of the apparatus.

Apparatus illustrating features of my invention is shown in theaccompanying drawings, in which:

FIG. 1 is a side elevational view, partly in section and with partsbroken away;

FIG. 2 is an end elevational view with parts partly broken away and insection and looking at the machine along lines 2-2 of FIG. 1;

FIG. 3 is a diagrammatic end elevational view, partly broken away, andillustrating the function of the mandrels in assemblying the heads intoa shell at the second station;

FIG. 4 is a detail fragmental sectional view taken generally along line4-4 of FIG. 3.

FIG. 5 is a view taken generally along line 5-5 of FIG. 4, certain ofthe parts being broken away and in section, and showing the mandrelsentering the grease tube, preparatory to being centered relative to theshell of the rolls;

FIG. 5a is a fragmental view partly in section illustrating theconfiguration of the ends of the grease tube and spring detent membersadjacent the ends of mandrels;

FIG. 6 is a detailed view, partly broken away. and in section, andshowing the position of the parts after the grease tube and heads havebeen brought into concentric relationship relative to the shell;

FIG. 7 is a detail fragmental view taken generally along line 77 of FIG.6;

FIG. 8 is a fragmental detail view, partly in section, showing theposition of the parts after the mandrels have pressed the heads into theends of the shell and have pressed the .grease tube into the openingstherefor in the heads;

FIG. 9 is a detail view taken generally along line 9-9 of FIG. 8;

FIG. 10 is a plan view, partly broken away, and showing some of thedetails of the pusher mechanism for inserting the grease tube into aroll shell, at the first station;

FIG. 11 is a detail sectional view taken generally along line 11-11 ofFIG. 10;

FIG. 12 is a detail view taken generally along line 12-12 of FIG. 11;

FIG. 13 is a fragmental detail side elevational view illustratingmechanism for feeding the heads, one at a time, in position to start theassembly process;

FIG. 14 is a detail sectional view taken generally along line 14-14 ofFIG. 13;

FIG. 15 is a vertical detail sectional view through the apparatusshowing the station where the ends of the shell are rolled or formedover the inserted heads, the view illustrating a headed shell inposition ready to be rolled over;

FIG. 16 is a view corresponding generally to FIG. 15 and showing theheading mechanisms in contact with the ends of the shell, preparatory torolling or forming over the ends of the shell;

FIG. 17 is a detail sectional view taken generally along line 17 of FIG.16;

FIG. 18 is a detail sectional view through one of the heads in assembledposition relative to the shell and grease tube, the assembly mandrelstill being in place; and,

FIG. 19 is a detail fragmental sectional view illustrating the relationof the outer side of the head with the rolled over end of the shell, ina completed assembly.

Referring now to the drawings for a better understanding of my inventionand particularly to FIGS. 1 and 2 it will be seen that the machinecomprises a base or frame supporting section indicated generally at 10.As stated before, the object is to feed to the machine, automatically orby hand, a plurality of roll shells indicated at 11, to insert therein agrease tube indicated at 12.and to place in each end of the shell,concentrically centered relative thereto and to the grease tube, a pairof the heads or hubs indicated at 13. Thus, and broadly stated, upon theframe 10 the mechanisms for receiving the parts just stated and forassembly-ing and finally forming over the head to hold them assembledare mounted and secured.

More in detail and viewing FIG. 2, it will be seen that the righthandside of the machine as viewed in that figure may be fixedly secured tothe frame or rails 10. The lefthand side of the machine as viewed inFIG. 2 may be movably supported on the rails for movement away from therighthand section of the machine, thus to accommodate shells 11 ofdifferent lengths, permitting the assembly or idler rolls and the likeof varying lengths. The lefthand side of the machine may be secured inadjusted position to the rails 10 by means of fasteners, bolts, setscrews or the like indicated at 14.

Mounted on the righthand section 16 of the machine, and facing thelefthand section 17 thereof, as viewed in FIG. 2, is a fixed workpiecesupporting rail 18. The rail 18 has notches or seats therein to receivethe roll shell as it is placed thereon, at the first station, namely,the station numbered A in FIG. 1 of the drawings. In similar manner theshiftable section 17 of the machine has a fixed rail 19 having aligned,corresponding seats to receive the roll shell at the station indicatedat A.

The rails 18 and 19 are provided at the stations indicated at B, C and Din FIG. 1 with similar, aligned arcu ate seats to accommodate the shells11 at the various stations when placed thereon as will be explained. Itmay also be added that for shells of different or varying diameters theradii of these seats or cutouts may be varied by the use of inserts. Themachine sections 16 and 17 are provided with vertically and horizontallyreciprocating transfer rails 21 and 22 together with means to operatethese in unison in the sense that they both move down at the same timeand reciprocate at the same time. Thus, there is provided a hydrauliccylinder 23 having a piston rod 24. The piston rod 24 is fastenedthrough a member 26 to a rack bar 27. The rack bar is supported forreciprocation in gear boxes 28 and 29. In each of the gear boxes aregears 31 and 32 in mesh with the teeth on the top of the bar 27. Also inmesh with the gears 31 and 32 are vertically disposed rack bars 33 and34. The rail 21 is thus supported at the upper ends of the rack bars 33and 34 and it will be apparent that when the piston rod 24 of hydrauliccylinder 23 reciprocates therein bars 33 and 34 and hence the rail 21 israised and lowered.

The cylinder 23, the gear boxes 28 and 29 all are supported on areciprocable bar-like member 37. The member 37 is supported for movementrelative to the base of the machine section 16 on grooved rollers 38 and39.

Mounted on the side of the lower portion of the base of section 16 ofthe machine is another hydraulic cylinder 41. The piston rod 42 of thecylinder 41 is connected by means of a member 43 to the reciprocablebar-like member 37. Therefore, when fluid is admitted under pressure toeither end of the cylinder 41 the piston rod 42 moves correspondingly,thus shifting the member 37 together with the rack bars 33 and 34 andhence the rail 21 to the right or left as viewed in FIG. 1.

The lefthand side 17 of the machine is provided with the identicalcylinders 23 and 41, the reciprocable member 37, the gear boxes 28 and29, rack bars 33 and 34. The cylinders 23 and 41 in both instances aredouble acting and control means, not shown, are provided for operatingthe two cylinders 23 and 41 in unison.

Therefore, the movable rails 21 and 22 move up and down together andreciprocate together, in order to transfer the workpieces, namely theshells, from stations A to station B to station C to station D. Theassembly just described in effect becomes a walking beam type oftransfer mechanism for the workpieces.

Starting again at station A of the apparatus which, as will beunderstood, is intended to cover the place where the shells 11 firstenter the machine it will be seen that the operation there carried outis to physically place the grease tube 12 inside the shell 11.Therefore, the shells 11 are supported on spaced apart rails 44 so that,when viewed in FIG. 1, the movable rails 21 and 22, when in loweredposition, move to the left under the influence of cylinder 41, raisingupwardly under the shell 11 resting at the lowermost end of the rails44. In other words, the movable rails 21 and 22 move from the positionof FIG. 1 to the left, positioning the notches therein at station Aunder the lowermost one of the row of shells 11, move it upwardly andthen back to the position shown in FIG. 1. In this position a shell 11is now in position at stationA and the rails 21 and 22 are raised abovethe level of the rails 18 and 19 so that the workpiece is supported inelevated position relative to the latter rails.

Mounted at one end of the shell while occupying station A is a V-shapedtrough member 46. See FIGS. 10, 11 and 12. This member is located at thelower end of a supporting member 47 on which is maintained a row of thegrease tubes 12. The bottom of the trough 46 is in direct alignment,axially, with a shell 11 while is occupies station A. The lowermost oneof the row of tubes 12 comes to rest against one edge of the trough 46.A solenoid 48 having its armature connected to a finger 49 pivoted at 51is adapted, when energized, to throw the tubes individually from theposition shown in FIG. 12 into the trough 46. Stated differently, assoon as the movable rails 21 and 22 position a shell 11 at station A thesolenoid 48 is energized, thus placing a grease tube in the trough orsupporting member 46.

Mounted at the end of the trough opposite station A is a cylinder 52having a piston rod 53. A pusher member 54 is mounted on the end of therod and slides in to V-shaped trough 46. Through automatic controls notillustrated, as soon as the shell 11 is in position on station A and assoon as the tube 12 is thrown over into the supporting member 46,cylinder 52 is energized thus to insert the grease tube into the shell11 by simply pushing it thereinto. It will be noted that initially thetube 12 rests in the bottom of the inside of the shell 11 as shown invarious of the figures, for instance, FIGS. 3 and 4.

As so far described the apparatus is now in position with a shell 11 atstation A, a tube 12 having been inserted thereinto while the shell wasresting in the notches of the fixed rails 18 and 19. However, in FIG.

1 I have shown movable rails 21 and 22, in raised position, ready to beshifted to the right, thus to move the thus assembled shell-grease tubefrom station A to station B.

Starting with the parts in the position of FIG. 1, the next operation inthe cycle is to move the assembled shell and tube occupying station A tostation B and to get a new shell from the supply rack 44 and to place iton station A. To accomplish this the first operation is to lower therack bars 34 by actuating cylinders 23. As soon as the rails 21- arelowered the assembled shell and tube will be resting on the notches inthe stationary rails 18 and 19 at station A. The next motion is toenergize I the cylinders 41 in unison so that their piston rods move tothe left as viewed in FIG. 1, bringing the notches or seats in the rails21 and 22 into position immediately below the lowermost one of theshells on the rack or supply mechanism. When thus positioned cylinders23 are energized to again raise the rails 19 and 21. This causes a newshell 11 to occupy the notches in the rails 19 and 21, at thelefthandmost side of FIG. 1 and at the same time for the notches in therails at station B to engage the assembled shell and grease tubeoccupying station A. Reverse energization of the cylinders 41 causes theparts to move back to the position of FIG. 1 transferring the assembledshell-grease tube to station B.

In axial alignment with the shell 1 1 occupying station B are hydrauliccylinders 61 and 62. These cylinders actuate mandrels 63 and 64 whichare secured to the respective piston rods carried by the cylinders 61and 62. As illustrated in various figures of the drawings the mandrelsthemselves are provided with reduced ends 66 and 67 which are adapted,as willbe explained, to enter into the ends of the grease tubes 11. Themandrels further are provided with sections 68 and 69 which are adaptedto enter into the openings of the heads 13, for the purpose of centeringthe heads relative to the shells ll. Pusher sections 63a and 64a areadapted to force the heads into the shell.

As detailed in FIG. 50, adjacent the end of each mandrel section 66 and67 I provide a spring biased ball type detent 70. The balls 70a engagethe ends of the grease tube upon inward movement of the mandrels,assuring that thetube is longitudinally centered in the shell. Further,the ends of the tubes are slightly informed as at 12a so that when thereduced ends of the mandrels enter the tube ends, the tube is correctlycentered relative to the shell.

The heads 13 are fed to station B by confining them in downwardlysloping trough-like holders 65, one located at each end of the shell 1 1which occupies station B. Asbest shown in FIG. 13 the troughs 65 areprovided at their lower ends with escapement mechanisms to permit theheads to roll, one at a time, from the ends of the troughs or holders toa position into axial alignment with the mandrels. Thus, the escapementmechanism may comprise a plate 71 pivoted at 72. The plate carries apair of outstanding pins 73 and 74. A spring 76 pivots the plate to aposition for pin 73 to engage a portion of the lowermost one of the rowof heads 13. However, upon actuating the plate 71 by pivoting it aboutits pivot point 72 the pin 73 withdraws from holding position,permitting the heads to roll to the position shown in FIG. 13, in axialalignment with the mandrels. When plate 71 is rocked clockwise as shownin FIG. 13, pin 74 acts as a temporary holder for the entire row ofgravity fed heads, permitting only one at a time to move from thelowermost end of the row to the position in alignment with the mandrels.When the plate returns again to the position of FIG. 13 one of the headshas escaped and has rolled downwardly to be stopped in position againstpins or the like 75. The plates 71 are actuated in unison by anysuitable form of mechanism'as for instance by. cams actuated by thecylinders 61 and 62.

Supported on'upper frame sections 81 and 82 of the machine arevertically arranged hydraulic cylinders 83 and 84. The piston rods ofthese cylinders carry hold down clamps 86 and 87 which, prior to theinsertion of the heads as just explained are lowered, thus to hold theshell firmly in place while the heading operation is being carried out.Obviously, prior to transferring the workpieces from station to station,theclarnps are released.

Recalling now that there is one of the troughs 65 at each end of theshell 11 at station B and that the movable rails 21 and 22 are in raisedposition, actuation of the cylinders 61 and 62 moves their respectivemandrels 63 and 64 toward each other. As shown in FIG. 3, the firstaction is for the mandrels to pass through the central openings in theheads 13 which occupy aligned positions relative thereto. Continuedmotion inwardly toward each other places the reduced ends 66 and 67 ofthe mandrels in the ends of the grease tube 12, as shown in FIGS. 5 and5a. The inwardly movement of the mandrels is momentarily stoppedwhereupon the movable rails 18 and 19 are lowered through the medium ofthe cylinders 23, whereby the parts assume the position shown in FIG. 6of the drawings. This places the grease tube and both'of the heads inaxial, concentric alignment relative to the shell 11. The cylinders 61and 62 are now again energized whereupon the parts move from theposition of FIG. 6 to the position of FIG. 8, that is with the headscompletely inserted in the shell and with the grease tube ends engagingthe tapered central, inner openings 13a of the heads 13. The cylinders61 and 62 are now reversely actuated withdrawing the mandrels. Themachine is now ready for another feeding and transfer operation, namely,ready for the movable rails to be moved downwardly, thence to the leftas viewed in FIG. 1, upwardly, and thence to the right as viewed inFIG. 1. i

The next operation is to form the ends of the shell over the peripheriesof the heads from the position shown in FIG. 18 to the position shown inFIG. 19. To this end the assembled parts are brought to station C. Themovable rails 21 and 22 are lowered thus to cause the shell to rest onthe stationary rails 18 and 19m station C. Hydraulic cylinders 91 and 92carry hold down clamp sections 93 and 94 in order to clamp the shellstationary at station C.

As shown particularly in FIGS. 15 and 16, at station C are shell endforming devices indicated generally by the numerals 96 and 97. Each ofthese comprises a rotating disc 98 carrying spaced forming rolls 99. Inaddition, the plates 98 are supported on the pistons of hydrauliccylinders, not shown, forming'a part of the mechanisms 96 and 97 so thatthe rolle 99 may be moved from the position of FIG. 15 to the positionof FIG. 16. That is to say, with the assembled parts clamped at stationC as shown in FIGS. 15 and 16, the forming mechanisms including theplates or discs 98 move inwardly from the position shown in FIG. 15 tothe position shown in FIG. 16 to engage the ends of the shell. Theplates and hence the rollers are now rotated,

rolling the end sections 11a overhanging the outer surfaces of the heads13 from the position shown in FIG. 18 to the positions shown in FIG. 19,thus completing the assembly of the heads, grease tubes and shell. Asbefore indicated with respect to the seats or notches in the rails, therelative positions of the rollers 99 On the plates'98 may be adjustedthus to accommodate shells of varying diameters.

The movable rails are now actuated again, thus picking up a new shell 11from the rack 44 and moving the thus completed, rolled over and finishedassembly to station D where it may be removed manually or by automaticmachinery as desired.

My invention is characterized by its simplicity of construction andaccuracy and speed of operation. I have not shown the various controlsfor operating and coordinating the parts of the apparatus because theconstruction and nature of these will be evident to those skilled in theart. Further, while I have laid particular stress on assemblying rollshaving the centrally disposed grease tube, it will be apparent that myapparatus is useful in assemblying only the heads.

While I have shown my invention in but one form, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications without departing from thespirit thereof.

What I claim is:

1. In apparatus for assemblying heads and grease tubes into a rollshell,

a. a first work station embodying means to place a grease tube in asubstantially horizontally disposed roll shell with the grease tubelying eccentrically in the roll shell,

b. means to move the thus related grease tube and roll shell from saidfirst station to a second station,

c. mandrels located at said second station and having grease tube androll head sections, disposed, when the mandrels move inwardly towardeach other, to pass through centrally disposed openings in the rollheads and to project into the ends of the grease tube,

d. means to move the mandrels inwardly first passing the grease tubesections through a pair of said heads and then inserting the grease tubesections into the ends of the grease tube,

e. means to bring the grease tube and roll shell into concentricrelation with each other, and

f. means to move the mandrel further toward each other, whereby theheads are pressed into the ends of the roll shell and the ends of thegrease tube are pressed into openings located adjacent the centers ofthe heads.

2. Apparatus as defined in claim 1 which includes a third work station,means to move the assembled roll shell, heads, and grease tube onto thethird station, and means at said third station to roll the ends of theroll shell over the peripheries of the heads, thereby to secure theheads in the roll shell.

3. Apparatus as defined in claim 1 in which there is means mounting oneof said mandrels and its operating instrumentalities for movement awayfrom the other thereof, thereby permitting the apparatus to operate uponroll shells of different lengths.

4. Apparatus for assemblying bored heads and a grease tube into a rollshell,

a. a first work station on which the roll shell is placed in asubstantially horizontal position,

b. means to place a grease tube inside the shell while at said firststation to lie eccentrically therein,

c. a second work station to which the roll shell carrying the greasetube is transferred,

(1. mandrels at said second station having inner reduced ends disposedto enter the ends of the grease tube and other sections adapted snuglyto fit into the bores of the heads,

e. means at the second station to position a head adjacent each end ofthe tube for passage therethrough of said reduced ends of the mandrelsand for engagement by said other sections of the mandrels within thebores of the heads,

f. means to move the mandrels into and out of the shell, whereby uponinward movement the heads are pushed into the ends of the shell and thegrease tube is connected concentrically with the heads,

g. a third work station at which there are means to form over the endsof the shell, whereby to secure the heads in the shell, and

h. transfer means for the shells common to all of said stations, wherebyas a shell is transferred from said first station to said second stationa shell is concomitantly transferred from said second to said thirdstation, etc.

5. Apparatus as defined in claim 4 in which said common transfer meanscomprises a pair of rails which extend under said work stations, meansto raise said rails in unison, to lower the same in unison, and to shiftthe same longitudinally in unison, whereby, the work pieces on saidvarious stations are transferred from one station to the other by thewalking beam motion of said rails.

6. Apparatus as defined in claim 4 in which at each of said stationsthere are stationary means for supporting the roll shells, and in whichat said second and third stations there are hold down means for engagingthe rolls while being operated upon.

7. Apparatus as defined in claim 4 in which there are means located atthe ends of the grease tube on said second station to position saidbored heads, one at a time, for the passage of said mandrelstherethrough.

8. For use in apparatus of the character described, a mandrel having aninner, reduced end of a size adapted to enter a grease tube to beassembled with heads and a roll shell, and a spring biased detent onsaid mandrel adapted, when the end of the mandrel is inserted into agrease tube, to engage the end of the tube and to push the tube toward alike mandrel simultaneously engaging the opposite end of the tube,whereby, when engaged between two such mandrels so equipped with saiddetents, the tube is centered prior to fully entry of either mandrelinto its respective end of the grease tube.

9. In apparatus for assemblying centrally bored heads into a roll shell,7

a. a work station on which the shell is placed in substantiallyhorizontal position,

b. means to position one of said heads at each end of the shell with thebores thereof generally aligned with the longitudinal axis of the shell,

0. a mandrel at each end of the shell with the ends thereof disposed topass into the bores of the heads and to press them into the ends of theshell,

d. another work station for receiving the assembled shell and heads, and

e. means at said last named work station efi'ective simultaneously toform over the ends of the shell about the peripheries of said heads,thereby to secure the heads in place.

1. In apparatus for assemblying heads and grease tubes into a rollshell, a. a first work station embodying means to place a grease tube ina substantially horizontally disposed roll shell with the grease tubelying eccentrically in the roll shell, b. means to move the thus relatedgrease tube and roll shell from said first station to a second station,c. mandrels located at said second station and having grease tube androll head sections, disposed, when the mandrels move inwardly towardeach other, to pass through centrally disposed openings in the rollheads and to project into the ends of the grease tube, d. means to movethe mandrels inwardly first passing the grease tube sections through apair of said heads and then inserting the grease tube sections into theends of the grease tube, e. means to bring the grease tube and rollshell into concentric relation with each other, and f. means to move themandrel further toward each other, whereby the heads are pressed intothe ends of the roll shell and the ends of the grease tube are pressedinto openings located adjacent thE centers of the heads.
 2. Apparatus asdefined in claim 1 which includes a third work station, means to movethe assembled roll shell, heads, and grease tube onto the third station,and means at said third station to roll the ends of the roll shell overthe peripheries of the heads, thereby to secure the heads in the rollshell.
 3. Apparatus as defined in claim 1 in which there is meansmounting one of said mandrels and its operating instrumentalities formovement away from the other thereof, thereby permitting the apparatusto operate upon roll shells of different lengths.
 4. Apparatus forassemblying bored heads and a grease tube into a roll shell, a. a firstwork station on which the roll shell is placed in a substantiallyhorizontal position, b. means to place a grease tube inside the shellwhile at said first station to lie eccentrically therein, c. a secondwork station to which the roll shell carrying the grease tube istransferred, d. mandrels at said second station having inner reducedends disposed to enter the ends of the grease tube and other sectionsadapted snugly to fit into the bores of the heads, e. means at thesecond station to position a head adjacent each end of the tube forpassage therethrough of said reduced ends of the mandrels and forengagement by said other sections of the mandrels within the bores ofthe heads, f. means to move the mandrels into and out of the shell,whereby upon inward movement the heads are pushed into the ends of theshell and the grease tube is connected concentrically with the heads, g.a third work station at which there are means to form over the ends ofthe shell, whereby to secure the heads in the shell, and h. transfermeans for the shells common to all of said stations, whereby as a shellis transferred from said first station to said second station a shell isconcomitantly transferred from said second to said third station, etc.5. Apparatus as defined in claim 4 in which said common transfer meanscomprises a pair of rails which extend under said work stations, meansto raise said rails in unison, to lower the same in unison, and to shiftthe same longitudinally in unison, whereby, the work pieces on saidvarious stations are transferred from one station to the other by thewalking beam motion of said rails.
 6. Apparatus as defined in claim 4 inwhich at each of said stations there are stationary means for supportingthe roll shells, and in which at said second and third stations thereare hold down means for engaging the rolls while being operated upon. 7.Apparatus as defined in claim 4 in which there are means located at theends of the grease tube on said second station to position said boredheads, one at a time, for the passage of said mandrels therethrough. 8.For use in apparatus of the character described, a mandrel having aninner, reduced end of a size adapted to enter a grease tube to beassembled with heads and a roll shell, and a spring biased detent onsaid mandrel adapted, when the end of the mandrel is inserted into agrease tube, to engage the end of the tube and to push the tube toward alike mandrel simultaneously engaging the opposite end of the tube,whereby, when engaged between two such mandrels so equipped with saiddetents, the tube is centered prior to fully entry of either mandrelinto its respective end of the grease tube.
 9. In apparatus forassemblying centrally bored heads into a roll shell, a. a work stationon which the shell is placed in substantially horizontal position, b.means to position one of said heads at each end of the shell with thebores thereof generally aligned with the longitudinal axis of the shell,c. a mandrel at each end of the shell with the ends thereof disposed topass into the bores of the heads and to press them into the ends of theshell, d. another work station for receiving the assembled shell andheads, and e. means at said last named work station effectivesimultaneOusly to form over the ends of the shell about the peripheriesof said heads, thereby to secure the heads in place.